The present invention is directed to novel compositions of urethane emollients, solubilizers, clarifiers and emulsifiers derived from monohydric alcohols and having no free isocyanate groups. These urethane emollients are substantially free of terminal hydroxyl groups and are derived from linear, branch-chained or aromatic monohydric alcoholic compounds of synthetic or natural origin. In particular aspects of the present invention, the use of monohydric urethane compounds according to the present invention, in fragrance compositions, will unexpectedly prolong the fragrance of a fragrance composition on the skin.
Standard emollients for the cosmetic, toiletry and personal care industries have been esters (monohydric) such as isopropyl myristate, butyl stearate, cetyl octanoate and isostearyl isostearate covering a wide breadth of molecular weights. Monohydric esters have also been manufactured from high molecular weight compounds such as behenic acid and behenyl alcohol which yield a solid ester useful as an emollient for increasing the melting point characteristics of a given formulation. Synthetic spermacetic waxes have been utilized for the past thirty years to replace the natural rare variety. Such products as cetyl palmitate, cetyl myristate and mixed cetyl esters have essentially replaced the use of spermacetic wax.
In the mid-seventies, there was a critical shortage of beeswax, and the synthesis of a synthetic version of this natural wax and emollients derived from this wax was sought. As one solution, the relatively high molecular weight dodecanedicarboxylic acid was esterified with a mixture of cetyl, stearyl and polyoxyethylene glycols to render a product that was found to be a suitable replacement. With the mixture of relatively high molecular weight alcohols and polyethers, the dicarboxylic acid of C12 yielded a perfectly usable product for skin applications-where natural beeswax had been used for numerous years.
For many years, monohydric alcohol diesters used in the cosmetic and personal care industries have been synthesized from such difunctional carboxylic acids as adipic, sebacic, azeleic, dodecanedicarboxylic acid and dimer acid, as well as anhydrides such as maleic, succinic and phthallic, among others. Based on the molecular weight of the difunctional carboxylic acid and the alcohol used, it was possible for the synthetic organic chemist to obtain a wide range of properties from these compositions, including, for example, dryness, oiliness, spreadability, lubricity, freezing point depression, insect repellency (e.g., dicapryl adipate), melting and slip point modification, emulsion synergism, solvency and color dispersion.
As the molecular weight of the dicarboxylic acid and corresponding alcohol increase, a greater degree of heaviness is imparted to the emollient, along with a higher degree of viscosity. As the degree of unsaturation of the alcohol used increases and becomes more olefinic in character, spreadability is enhanced. For example, diesters derived from oleyl or linoleyl alcohols have a greater degree of spreadability than does a corresponding diester derived from stearyl or isostearyl alcohol.
It is possible to further influence the melting point and indeed the viscosity of a diester through the use of branched rather than linear structures. With the introduction of an ether linkage, the liquidity of a given diester is also enhanced. Diesters made from ethoxylated and/or propoxylated adducts of alcohols have also been used as emollients and emulsifiers.
As a result of molecular weight and structure, diisopropyl adipate has been found to be an extremely dry ester with excellent solvency characteristics. Because of its physical properties, diisopropyl adipate finds use in products ranging from floating bath oils, after shaves, creams, lotions, deodorants, pre-electric shave lotions, to antiperspirants. Diisopropyl adipate has been widely used for numerous years in these applications because of the availability of raw materials and relatively low production cost. Diisostearyl adipate, on the other hand, is a relatively heavy, water white diester with little or no odor that imparts a luster and sheen to the skin and, as a result of its molecular weight and viscosity, has a tendency to linger on the skin. Dicapryl adipate is a diester derived from natural sources (through the cracking of castor oil to yield caprylene, then conversion to the corresponding alcohol) which has been found to exhibit insect repellency and has met with huge success in repellents for use in human and animal products. Diesters derived from dimer acids, such as diisopropyl dimerate and diisostearyl dimerate, in addition to being excellent, long lasting emollients because of their relatively high molecular weight, were shown to add anti-irritation characteristics to given skin formulations.
Typical end-use applications of diesters of dicarboxylic acids in the personal care, cosmetic as well as toiletry industries include: skin care products, eye makeups, body shampoo, stick deodorants, protective skin formulations, lipsticks, lip glosses, pre-electric and after shave lotions, after-bath splashes, shampoos and rinses, presun and sun products, antiperspirants and sunscreens.
It is an object of the present invention to provide fragrance compositions which exhibit enhanced fragrance values and prolong the fragrance of a composition on the skin of a user.
It is a further object of the present invention to provide urethanes of monohydric alcohols, which, when added to compositions, may function to reduce, counteract and neutralize malodors on the skin or in a closed environment such as a home, a bedroom, a bathroom, or a boat.
These and/or other objects of the invention may be readily gleaned from the description of the invention, which follows.
The present invention relates to a dimeric urethane compounds derived from monohydric alcohols, generally fatty alcohols, and a diisocyanate according to the following reaction scheme: 
wherein R1 is selected from the group consisting of saturated, unsaturated, aromatic or halogen substituted linear, cyclic, aromatic or branch-chained hydrocarbons and R2 is a linear, cyclic, aromatic, branch-chained alkyl, aminoalkyl, amino alkanol or alkoxide group ranging from two to 500 carbon atoms, preferably two to 50 carbons, more preferably 6 to 36 carbons, even more preferably from about 6 to 22 carbons, said urethane compound being substantially free of terminal hydroxyl groups.
Compounds according to the present invention exhibit primary utility as emollients, wetting agents, dispersants, lubricants, plasticizers, stabilizers, emulsifiers, clarifying agents, solubilizing agents and adhesion and melting point modifiers in formulations of cosmetic, toiletry and personal care products. The emollient properties of compounds according to the present invention are primarily due to the hydrophobic nature of the fatty alkyl groups, which maintain a desirable moisture balance as it softens and soothes the skin and related mucous membranes.
By proper selection of the diisocyanate and monohydric alcohol, it is possible to obtain a wide variety of properties in the resultant urethane compound, ranging from such characteristics as a glasslike, resinous product suitable as an extremely heavy emollient and replacement for diisostearyl adipate to a solid product such as an arichidyl urethane suitable as a substitute for beeswax in formulations. The monohydric alcohols reacted to produce the compounds with a diisocyanate group according to the present invention may be synthetically or naturally derived.
One of the more innovative properties of compounds according to the present invention is the stability of the dimeric urethane of the monohydric alcohols over a wide pH range and temperature. Under conditions causing the prior art diesters of corresponding alcohols to readily decompose, their urethane counterparts will remain relatively stable. Consequently, the dimeric urethanes are versatile in their chemical properties, and are unique in their ability to resist hydrolysis and thermal decomposition. Stable storage compounds (those which are resistant to degradation at variable pH or at elevated temperature) may be readily formulated using compounds according to the present invention.
Other properties of the compounds of the present invention which make them superior to the diesters currently used may include:
Water-white color;
Extremely low order of irritation and toxicity;
Substantial absence of hydroxyl groups;
Excellent compatibility in cosmetic and toiletry formulations;
Solubility in sunscreens, i.e., octacrylene, octyl salicylate, octylmethoxy cinnamate, menthyl anthranilate, PABA;
Solubility in mineral oil;
Solubility in vegetable oil;
Solubility in silicone fluids;
Solubility in most esters;
Solubility in most alcohols;
Essentially odorless;
Substantially Non-rancidifying;
Prolong fragrance (odor retention) on the skin;
Counteract and Neutralize malodors on the skin for extended periods.
Another aspect of the present invention relates to compositions comprisng the previously described urethane compounds in combination with about 0.5% to about 100% by weight of a free or unreacted monohydric alcohol. The inclusion of the monohydric alcohol may be used as a viscosity control additive or as a solubilizing agent in this aspect of the present invention. Thus, in this aspect of the present invention, a composition for use in cosmetic, toiletry and personal care products consists essentially of about 0.25% to about 50% by weight of a free monohydric alcohol and about 50% to about 99.75% by weight of a urethane compound according to the present invention. Preferably, the composition according to this aspect of the present invention consists essentially of about 0.5% to about 25% by weight, more preferably about 1% to about 15% by weight free monohydric alcohol.
Urethane compounds according to the present invention may be used in personal care, toiletry or cosmetic compositions in amounts ranging from about 0.05% to about 35% by weight, preferably about 0.5% to about 25% by weight, more preferably about 1% to about 15% by weight of the final personal care, toiletry or cosmetic composition. In fragrance aspects of the present invention, the amount of urethane compound according to the present invention which is included in fragrance compositions ranges from about 0.05% to about 15% by weight, more preferably about 0.1% to about 10% by weight, more preferably about 0.1% to about 3% by weight of the final composition. Urethane compounds according to the present invention find particular use in compositions which utilize pH variability or heat for manufacturing or utilize elevated temperatures during use (for example, in the case of shampoos, conditions, sunscreens, etc.). Storage stability of the final composition is another feature which may be markedly improved by the inclusion of effective amounts of the present compounds.
The term xe2x80x9cmonohydric alcoholxe2x80x9d is used throughout the specification to describe a linear, cyclic, aromatic or branch-chained hydrocarbon having a single hydroxy group located at one terminus of the molecule and/or a linear, cyclic or branched-chain amine having a single hydroxy group located at one terminus of the molecule and includes such amine-containing compounds as monoethanolamine, aminoethylethanolamine, diglycolamine, acetylated monoethanolamine, among numerous others. The amine may be a primary, secondary or tertiary amine. The compounds may be unsubstituted or halogen substituted. The inclusion of an amine may be advantageously employed because of the tendency of the amine to substantially protonate and become more water soluble at pH""s below about 10.0. In addition, the presence of the amine group, due to its cationic nature, imparts a more substantive character to the compound. In a preferred embodiment of the present invention, the length of the monohydric alcohol is between 2 and 200 carbons. In more preferred embodiments, the monohydric alcohol ranges from about 2 to about 50 carbons and in even more preferred embodiments, the monohydric alcohol ranges from about 6 to about 36 carbons, even more preferably about 6 to about 22-24 carbons. Exemplary monohydric alcohols for use in the present invention include, range for example, from ethyl through C50 alcohols, more preferably C6 through C36, even more preferably C6 through C22 and include, for example, ethanol, isopropanol, butanol, isobutanol, amyl alcohol, benzyl alcohol, isoamyl alcohol, hexanol, isohexanol, heptanol, n-octanol, 2-ethylhexanol, isooctanol, n-nonanol, isononyl alcohol, n-decanol, isodecanol, n-lauryl alcohol, tridecanol, n-myristyl alcohol, n-cetyl alcohol, isocetanol, n-stearyl, isostearyl alcohol, octyldodecanol, archidyl alcohol, alcohols up through C50, more preferably up to C36, ethoxylated and/or propoxylated versions of the above-described alcohols, phenoxyethanols and ethoxylated and/or propoxylated nonyl phenols. Numerous additional monohydric alcohols also may be used in the present invention.
The term xe2x80x9cdiisocyanatexe2x80x9d is used throughout the specification to describe a linear, cyclic or branch-chained hydrocarbon having two free isocyanate groups. The term xe2x80x9cdiisocyanatexe2x80x9d also includes halogen substituted linear, cyclic or branch-chained hydrocarbons having two free isocyanate groups. Exemplary diisocyanates include for example, isophorone diisocyanate, m-phenylenediisocyanate, p-phenylene diisocyanate, 4,4-butyl-m-phenylene diisocyanate, 4-methoxy-m-phenylene diisocyanate, 4-phenoxy-m-phenylene diisocyanate, 4-chloro-m-phenylene diisocyanate, toluenediisocyanate, m-xylylenediisocyanate, p-xylylenediisocyanate, 1,4-napthalenediisocyanate, cumene-14,-diisocyanate, durenediisocyanate, 1,5-napthylenediisocyanate, 1,8-napthylenediisocyanate, 1,5-tetrahydronapthylenediisocyanate, 2,6-napthylenediisocyanate, 1,5-tetrahydronapthylenediisocyanate; p,p-diphylenediisocyanate; 2,4-diphenylhexane-1,6-diisocyanate; methylenediisocyanates; ethylenediisocyanates; trimethylenediisocyanate, tetramethylenediisocyanate, pentamethylenediisocyanate, hexamethylenediisocyanate, nonamethylenediisocyanate, decamethylenediisocyanate, 3-chloro-trimethylenediisocyanate and 2,3-dimethyltetramethylene diisocyanates.
The term xe2x80x9cemollientxe2x80x9d is used throughout the specification to describe compounds according to the present invention which soften, lubricate and moisturize the skin as aswell as sooth irritation to the skin and mucous membranes, i.e., they are soothing to the skin.
The term xe2x80x9cemollient effective amountxe2x80x9d is used throughout the specification to describe concentrations or amounts of compounds according to the present invention which are included in cosmetic and personal care products according to the present invention which provide effective emollient character for treating keratinous and epithelial tissue, including skin, nails (ungual tissue), hair and mucous linings of the mouth and nasal passages.
The term xe2x80x9ceffective amountxe2x80x9d is used throughout the specification to describe concentrations or amounts of compounds according to the present invention which are effective in conveying desired traits such as prolonging fragrance values in fragrances and counteracting and/or neutralizing malodors for extended periods of time (i.e., for a period of at least about 2 hours, preferably for at least 6 hours, even more preferably for a period of at least about 24 hours). In certain cases, fragrance values may be extended in certain aspects of the present invention for periods of at least 2 days up to 10 or more days, depending upon the fragrance used.
The term xe2x80x9cfragrance componentxe2x80x9d is used throughout the specification to describe a composition, generally known in the art as a perfume or toiletry composition, which emits a pleasant odor as its principal purpose or main feature. Fragrance components according to the present invention comprise a fragrance oil or compound in an amount ranging from about 5% to about 100% by weight, alternatively about 10% to about 99.95%, alternatively about 15% to about 99.95%, and alternatively at least about 25% by weight, optionally in combination with a diluent (i.e., a solvent such as water or an alcohol for example ethanol, preferably a polyhydric alcohol such as glycols, for example propylene glycol, hexylene glycol or dipropylene glycol (when included) ranging from about 0.05% to about 95% by weight and optionally, a surfactant such as a Tween(trademark) or Span(trademark) surfactant (preferably, Tween(trademark) 20 to render the fragrance oil water soluble/dispersible), among other surfactants in an amount ranging from about 0.05% to about 10% by weight, preferably no more than about 5% within this range, to make the oils within the fragrance composition more water soluble.
Fragrance components as described above are then mixed with a monohydric urethane compound according to the present invention to produce a final fragrance composition, wherein the amount of said urethane compound ranges from about 0.05% to about 15% by weight, more preferably about 0.1% to about 10% by weight, even more preferably about 0.1% to about 3% by weight, the remainder of the fragrance composition comprising the fragrance component as described above.
Surfactants for optional inclusion in fragrance compositions according to the present invention include the Tween(trademark) surfactants (a polysorbate type surfactant which includes oleate esters of sorbitol and its anhydrides copolymerized with a number of moles of ethylene oxide per mole of sorbitol and sorbitol anhydride, including for example, a sorbitan mono-9-octadecenoate poly(oxy-1,2-etheandiyl) derivative otherwise known as Tween(trademark) 80 or Polysorbate 80) and Span(trademark) surfactants, which are partial esters of common fatty acids, such as lauric acid, palmitic acid, stearic acid and oleic acids and hexitol anhydrides such as hexitans and hexides, derived from sorbitol. Preferred Span(trademark) surfactants include Span 20, wherein the sorbitan fatty ester is based upon laurate ester, Span 60, wherein the ester is based upon stearate ester and Span 80, wherein the ester is based upon oleic ester. The hydrophilic character of the Span(trademark) surfactants is supplied by free hydroxyl and oxyethylene groups, while the lipophilic character is provided by the long chain fatty groups.
The Tween(trademark) or polysorbate type surfactants are oleate esters of sorbitol and its anhydrides copolymerized with a number of moles of ethylene oxide per mole of sorbitol and sorbitol anhydride. The Tween(trademark) surfactants are soluble or well dispersible in water. Preferred Tween(trademark) surfactants include a sorbitan mono-9-octadecenoate poly(oxy-1,2-etheandiyl) derivative otherwise known as Tween(trademark) 80 or Polysorbate 80. 
The Span(trademark) surfactants, which may be optionally included in the present compositions of the present invention as secondary surfactants (the polysorbate surfactants are the preferred primary surfactants), are partial esters of common fatty acids, such as lauric acid, palmitic acid, stearic acid and oleic acids and hexitol anhydrides such as hexitans and hexides, derived from sorbitol (see below). In the case of Span 20, the sorbitan fatty ester is based upon laurate ester. In the case of Span 60, the ester is based upon stearate ester and in the case of Span 80, the ester is based upon oleic ester. The hydrophilic character of the Span(trademark) surfactants is supplied by free hydroxyl and oxyethylene groups, while the lipophilic character is provided by the long chain fatty groups. The Span(trademark) surfactants tend to be oil soluble and dispersible or insoluble in water. 
The term xe2x80x9cfragrance oilxe2x80x9d or xe2x80x9cfragrancexe2x80x9d is used throughout the specification to describe any one or more of the various esters, ketals, acetals, hemiacetals, alcohols, ketones, lactones, nitrites or related organic compounds (preferably, with a carbon chain length of 12, i.e., C12 or less to promote volatility), including oils of natural plants such as rose, geranium, etc., as well as extracts of made from the sex glands of animals such as deer, beaver, etc. which are aromatic in nature and exude a fragrance because of the volatility of the compound. A fragrance composition according to the present invention may comprise as few as two fragrance oils or compounds and may contain 150 or more fragrance oils or compounds. Fragrance oils for use in the present invention are numerous and include large number of possible compounds for example, including those which are set forth in the fragrance examples which are set forth in detail below.
Improved fragrance compositions according to the present invention comprise a fragrance component (as otherwise described above) in combination with at least one urethane compound according to the present invention: 
wherein R1 is selected from the group consisting of saturated, unsaturated, aromatic or halogen substituted linear, cyclic, aromatic or branch-chained hydrocarbons ranging from about 2 to 24 carbons, preferably about 6 to 22 carbon atoms (most preferably R1 is an isophorone group), and R2 is a linear, cyclic, aromatic, branch-chained alkyl, aminoalkyl, amino alkanol or alkoxide group ranging from two to 36 carbons, more preferably from about 6 to 24 carbons, said urethane compound being substantially free of terminal hydroxyl groups, the amount of the fragrance component ranging from about 85% to about 99.95% by weight, preferably about 90% to about 99.9% by weight, more preferably about 97% to about 99.9% by weight and the amount of the urethane compound ranging from about 0.05% to about 15% by weight, preferably about 0.1% to about 10% by weight, more preferably about 0.1% to about 3.0% by weight. In preferred aspects of the present invention, R2 is an alkyl or aminoalkyl group. Compositions according to the present invention exhibit a prolonged fragrance value as well as an ability to counteract or neutralize malodors for extended periods of time. Thus, compositions according to the present invention are useful as fragrance compositions for application to the skin or other keratinous tissue of a mammal, including a human or for air fresheners or deodorizers for use in a closed environment such as a home, bedroom, bathroom, boat or other closed environment.
The term xe2x80x9csubstantially freexe2x80x9d is used throughout the specification to describe preferred urethane compounds according to the present invention which essentially contain no free terminal hydroxyl groups, i.e., they appear to be all reacted and analytical methods do not detect terminal hydroxyl groups other than those which may appear as slight impurities in the compounds of the present invention. The term xe2x80x9csubstantially freexe2x80x9d is not a theoretical absolute value, but merely reflects the practical limits of detecting free terminal hydroxyl groups in the present invention.
Compounds according to the present invention may be prepared by synthetic methods known in the art. A general synthetic scheme involves reacting at least two molar equivalents of a monohydric alcohol, generally a fatty alcohol, with a diisocyanate in the presence of heat and a catalyst such as stannous octanoate. Each isocyanate moiety is thereby converted to a urethane moiety with the aliphatic portion of the alcohol extending out from the urethane moiety. The free alcohols are all reacted with isocyanate groups to form urethanes, leaving substantially no free hydroxyl groups at the ends of the side chains (i.e. the compounds of the present invention are not hydroxyl-terminated). Preferably, there are no free hydroxyl moieties anywhere on the side chains of the compounds of the present invention. Illustrative examples of the synthesis of particular compounds follow below.
Compounds according to the present invention may be used as emollients for keratinous and epithelial tissue such as hair, ungual tissue (nails), skin and related mucous membranes. By addition of an emollient effective amount of these urethanes, formulations for use as cosmetic, toiletry or personal care products will acquire the desirable soothing characteristics. In addition, compounds according to the present invention are included in fragrance compositions as fragrance extenders by increasing or prolonging fragrance values and/or counteracting or neutralizing malodors. This is an unexpected characteristic of the present invention. Thus, compositions according to the present invention are particularly useful as fragrances for application to the skin of a mammal (including a human) or for use as fragrance compositions in air fresheners or other compositions which are used to deodorize and/or freshen the air in closed environments (i.e., not exposed to the atmosphere in a direct, open manner) such as homes, bathrooms, automobiles, boats, basements, etc.
Effective amounts of the urethanes of the present invention may also serve as emulsifiers, clarifiers and melting point modifiers in formulations of the personal care, cosmetic and toiletry industries, especially where diesters of dicarboxylic acid have been used in the past or in formulations of silicone fluids, in which these novel urethanes are soluble. The urethanes of the present invention have superior stability at high or low pH values and thermal variations, where the mono- and diesters of the prior art are subject to degradation. Consequently, the dimeric urethanes of the present invention provide a significantly greater degree of stability and flexibility in formulations than do the diesters. It is an unexpected result that the urethane compounds of the present invention would provide the variety of characteristics exhibits with a high degree of stability (to variations in pH and temperature). In addition, the present compounds are compatible with biological systems and are generally substantially non-toxic (i.e., they can be used safely in cosmetic, toiletry and personal care products).
The present compounds instill a great degree of flexibility in formulating personal care products. The viscosity of a formulation for cosmetic, toiletry or personal care use can be dictated by adding an effective amount of a compound of the present invention with an appropriate length side chain. Shorter side chains, i.e., those derived from monohydric alcohols of about 1 to 3 carbon atoms product materials of a resinous consistency. Side chains of 6 to 10 carbon atoms produce compounds of lower viscosity, with maximum viscosity of approximately 1000 centipoise units. Longer side chains containing monohydric alcohols of about 12 to 500 carbon atoms lead to higher viscosity, with compounds containing about 6 to 24 carbon atoms leading to viscosities within the range of approximately 4000 to 5000 centipoise units. Those of ordinary skill engaging in routine experimentation will be able to readily identify the proper side chain length for any desired viscosity. Similarly affecting the viscosity and adhesion is the degree of branching of the side chains of the urethane; with increasing branching for the same number of carbon units, the viscosity decreases. In addition, as the amount of unsaturation in a side chain increases, the viscosity of the dimeric urethane from which such monohydric alcohol is derived will decrease. The ideal properties of emmolience are anticipated in compounds according to the present invention where the monohydric alcohol (side chain of the dimeric urethane) from which the present compounds are derived) comprise about 6 to 24 carbon atoms, wherein the side chain is preferably an unsaturated hydrocarbon.
The viscosity of the compounds of the present invention, and, therefore, the formulations in which they are used, may also readily be adjusted by adding about 0.5% to about 100% by weight of the dimeric urethane, preferably about 1% to about 50% by weight, more preferably about 2% to about 30% by weight, even more preferably about 10% to about 25% by weight of excess unreacted monohydric alcohols to the compounds of the present invention. These unreacted alcohols will reduce the viscosity of the compound or formulation in which they are included for modifying the characteristics of cosmetic, toiletry or personal care products according to the present invention. Unreacted alcohols in the formulation may readily be obtained by including an excess of monohydric alcohol to the diisocyanate before synthesis of the urethane. Alternatively, the addition of monohydric alcohol to the compounds of the invention after synthesis may also represent an appropriate option.
In the present invention, a dimeric urethane compound according to the present invention which is derived from a C6 to C10 monohydric alcohol is considered a xe2x80x9clightxe2x80x9d emollient, i.e., an emollient which has a low viscosity falling within the range of about 10 centipoise units to about 1000 centipoise units. Light emollients are preferably included in personal care products where lower viscosity is a desirable feature. Such personal care products include shampoos, conditioners, fragrances, lotions including sunscreens and suntan lotions. xe2x80x9cHeavyxe2x80x9d emollients are those dimeric urethane compounds which are derived from monohydric alcohols which are C12 or greater in length. Heavy emollients generally have a high viscosity which is above 1000 centipoise units, and preferably fall within the range of about 2000 centipoise units to about 5,000 centipoise units. It is noted that emollients which have viscosities which fall at the upper range of viscosity, i.e., about 5,000 centipoise units and above, in order to be readily workable and useful in the present invention, may need to have their viscosities adjusted by including free monohydric alcohol in an amount up to about 100% by weight of the dimeric urethane compound according to the present invention. Heavy emollients find use in cosmetics and personal care products which require higher viscosities, for example, in creams, ointments, pastes and solid cosmetics such as make-up and lipstick products, deodorants/anti-perspirants, among numerous others.
The following examples of compounds according to the present invention have been prepared:
Monoderm I-24: the reaction product of 2-decyltetradecanol with isophoronediisocyanate (IPDI);
Monoderm I-20: the reaction product of octyldodecanol with IPDI;
Monoderm I-18: the reaction product of isostearyl alcohol with IPDI;
Monoderm I-180: the reaction product of oleyl alcohol with IPDI;
Monoderm I-16: the reaction product of isocetyl alcohol with IPDI;
Monoderm I-14: the reaction product of isotetradeceyl alcohol with IPDI;
Monoderm I-12: the reaction product of isodecyl alcohol with IPDI;
Monoderm N-12: the reaction product of dodecanol with IPDI;
Monoderm 12-3: the reaction product of laureth-3 alcohol with IPDI;
Monoderm N-10: the reaction product of decyl alcohol with IPDI;
Monoderm I-9: the reaction product of isononanol with IPDI;
Monoderm I-8: the reaction product of octanol with IPDI;
Monoderm I-6: the reaction product of isohexyl alcohol with IPDI;
Monoderm I-8-C4: the reaction product of Capryl alcohol with IPDI;
Monoderm I-3: the reaction product of isopropanol with IPDI;
Monoderm DGDE: the reaction product of glycol ether dimer with IPDI;
Monoderm N18-100: the reaction product of PEG-100 stearyl ether dimer with IPDI;
Monoderm N4-100: the reaction product of PEG-100 butyl ether dimer with IPDI.
The examples above all use isophorone diisocyanate, but the following isocyanates are among those which may be used to yield acceptable products: m-phenylenediisocyanate; p-phenylene diisocyanate; 4,4-butyl-m-phenylene diisocyanate; 4-methoxy-m-phenylene diisocyanate; 4-phenoxy-m-phenylene diisocyanate; 4-chloro-m-phenylene diisocyanate; toluenediisocyanate; m-xylylenediisocyanate; p-xylylenediisocyanate; 1,4-napthalenediisocyanate; cumene-14,-diisocyanate; durenediisocyanate; 1,5-napthylenediisocyanate; 1,8-napthylenediisocyanate; 1,5-tetrahydronapthylenediisocyanate; 2,6-napthylenediisocyanate; 1,5-tetrahydronapthylenediisocyanate; p,p-diphylenediisocyanate; 2,4-diphenylhexane-1,6-diisocyanate; methylenediisocyanates; ethylenediisocyanates; tri, tetra, penta, hexa, nona and decamethylene diisocyanates; 3-chloro-trimethylenediisocyanate; and 2,3-dimethyltetramethylene diisocyanates.
In another aspect, the present invention also relates to a method of decreasing the viscosity of a urethane compound to be added to a toiletry, cosmetic or personal care product comprising adding a viscosity reducing effective amount of at least one unreacted monohydric alcohol to the urethane compound(s) in an amount ranging from about 0.5% to about 100% by weight of the urethane compound. The compositions which consist essentially of a urethane compound and monohydric alcohol may be added to any number of cosmetic, toiletry and personal care formulations to increase the workability and reduce the viscosity of the formulation.
The present invention also relates to the unexpected discovery that the inclusion of effective amounts of a monohydric urethane compound according to the present invention (preferably, wherein R2 is a C6-C24 (advantageously C6-C22 within this range) linear, branch-chained, cyclic or aromatic alkyl or amino alkyl group, preferably an alkyl group), in a fragrance composition will significantly prolong the fragrance value of the fragrance composition compared to a composition which does not include the monohydric urethane compounds according to the present invention. While not being limited by way of theory, it is believed that the compounds according to the present invention create a favorable interaction with fragrance molecules and slowly release the fragrance molecules from the composition over time thus increasing the composition""s fragrance value, a characteristic which relates to the ability of the composition to exhibit a characteristic fragrance over time. In this method according to the present invention, a monohydric alcohol urethane compound is added to a fragrance composition in an amount ranging from about 0.05% to about 15% by weight, preferably about 0.1% to about 10% by weight, more preferably about 0.1% to about 3.0% by weight. In alternative embodiments related to the ability of the urethane compound to counteract and/or neutralize malodor, while not being limited by way of theory, it is believed that the urethane compounds favorable interacts and adsorbs the malodorous compounds, thus reducing or eliminating the ability of the malodorous compound to volatilize and create the malodor. Thus, the present invention also relates to methods of reducing or counteracting malodors in a fragrance composition using urethane compounds according to the present invention.
Listed below are studies comparing the stability of diesters derived from dicarboxylic acids in comparison to difunctional urethanes:
The following stability study was conducted to determine the structural stability of dimeric urethane compounds according to the present invention compared to mono- and diesters under conditions of pH and thermal variation. Because the decomposition products of the mono- and diesters are alcohol and acid, the degree of decomposition may be accurately determined by measuring the acid value. The measurable decomposition product of the urethane compound is alcohol, which is accurately measured by determining the hydroxyl value.
The Following Mono- and Diester Products were Tested
Isocetyl salicylate (ICSA);
Diisopropyl adipate (DIA);
Diisopropyl dilinoleate (DID);
The Following Urethane Products were Tested
2-ethyl hexanol dimer with IPDI (I-8);
Isocetyl alcohol dimer with IPDI (I-16);
Isostearyl alcohol dimer with IPDI (I-18);
Octyl dodecanol dimer with IPDI (I-20);
Eicosanyl alcohol dimer with IPDI (I-24);
III. Procedure for Determining Mono- or Diester Stability
The following steps were performed on each ester sample:
(1) Run acid value test;
(2) Into three ground glass Erlenmeyer flasks, weigh a 20 g sample of the ester.
(3) Into each flask, pipette 50 ml of a neutralized (to phenolpthalein end point) Solution of 70% Isopropanol in water. Boiling stones are added.
(4) Connect flask A to a 4-5 ft. Reflux condenser and heat so that it refluxes 1 ft. High (to approximately 80-90xc2x0 C.). After connecting flasks A, B and C, proceed to step (7).
(5) Add 10% Aq. Hcl solution to adjust pH of solution in flask B to pH=2.5-3.5. See step (4).
(6) Add 20% Aq. KOH Solution to adjust pH of solution in Flask C to pH=13-14. See step (4).
(7) Reflux for 1 hour.
(8) For each flash, A, B and C, disconnect condenser. Pour Alcoholic solution into wide diameter beaker (A, B and C). Add spin bar. Under hood, evaporate alcohol/water solvent on spin/hot plate until it is reduced to 80-90% of volume. Put beaker in oven (105xc2x0 C.) until remainder of alcohol/water is evaporated.
(9) Run acid value test on solution in beaker A.
(10) Wash solution in beakers B and C twice with water. Add 20 ml of hot water, mix, add to separatory funnel, drop bottom water layer. Put beakers back into oven into water is evaporated.
(11) Run acid value test on solution in beaker B and solution in beaker C. The acid value method used is A.O.C.S. (AMERICAN OIL CHEMISTS SOCIETY)
T.M. #Cd3a-63.
SAMPLE SIZE: 10 g=0.1 mg
KOH, Aq.: 0.1213N
KOH Aq.: 0.4724N
IV. Procedure for Urethane Stability
The following steps were performed on each urethane sample:
(1) Run hydroxyl value test.
(2) Follow steps 2-8 for mono- and diester (above).
(3) Run hydroxyl value test on solution in beaker A.
(4) Perform step 10, from above.
(5) Run hydroxyl value test on solution in Beaker B and Beaker C.
Hydroxyl value method: A.O.C.S. (AMERICAN OIL CHEMISTS SOCIETY)
TM#Cd 13-16.
SAMPLE SIZE=10 g=0.1 mg
KOH, Aq.=0.4724N
V. Summary of Results
Summary of Results
VI. Conclusion of Testing
Under conditions of this study, that is,
xe2x80x9cAxe2x80x9d: Product in alcoholic/water solution, heat
xe2x80x9cBxe2x80x9d: Product in alcoholic/water solution, heat, pH=2.5-3.5
xe2x80x9cCxe2x80x9d: Product in alcoholic/water solution, heat, pH=13-14
The mono and diesters demonostrated less stability than did the dimeric urethane compounds of the present invention to heat and pH chances, whether those changes are primarily acidic or basic.
The present invention is now described, purely by way of illustration, in the following examples. It will be understood by one of ordinary skill in the art that these examples are in no way limiting and that variations of detail can be made without departing from the spirit and scope of the present invention.
In performing the following syntheses, the following reagents were used. Solvents, where used, are generally distilled prior to use. 3-isocyanatomethyl-3,5,5-trimethyl cyclohexylisocyanate (IPDI) was obtained from Hxc3xcls America, Inc., Piscataway, N.J. The monohydric alcohols used in these experiments for condensation with the diiosocyanate were generally obtained from Vista Condea, Houston, Tex. Sources of other materials are indicated in the appropriate experimental section.